A. Field of the Invention
The device of the present invention relates to a new and improved inner member for controlling the flow of fluid through a flow regulator.
B. Description of the Prior Art
In industries such as the natural gas industry where flow of fluid under varying pressures is desired to be controlled, fluid flow regulators of the type that compress a solid elastomeric inner element or member in order to enlarge the outer periphery of the element thereby reducing the flow area through the regulator have been employed. These prior art regulators include a housing mounted within the fluid system. Within the housing a reciprocating cylinder is positioned, and controlled by an external master piston. Within the regulator is a stationary member that is adjacent the piston. The elastomeric inner element is positioned between the piston and the stationary member.
To reduce the flow through the regulator and thus the fluid system, the cylinder is actuated by the master piston compressing the inner member and radially bulging the elastomeric element to reduce the cross-sectional flow area through the regulator. Fluid flow through the system is controlled in this manner. Examples of such regulators and elements are disclosed in U.S. Pat. No. 2,917,269--Welker, U.S. Pat. No. 3,368,787--Sachnik et al, and U.S. Pat. No. 3,380,470--Culpepper, Jr. et al.
These prior art valves are particularly desirable since they are very effective in providing a wide range of flow control at low noise levels. In the larger sizes of inner elements and flow regulators employed in large gas lines containing fluid under substantial pressure, particularly where applications require regulation to a relatively low downstream pressure, deterioration of the outer surface of the prior art solid inner element occurs resulting in reduced life. While replacement of the inner element is easily accomplished, the shut down time of the piping system necessary to accomplish this is undesirable.